body{
    background-color: rgb(151, 148, 148);
}
.div{
    overflow: hidden;
}
.cl{
    clear: both;
}
.wrapper{
    width: 98%;
    background-color: #fff222;
    margin: 0 auto;  /*水平居中 */
}
.header{
    width: 100%;
    background-color: rgb(119, 175, 239);
    margin: 0 auto;
    min-height: 200px;
}

.main{
    width: 100%;
    background-color: #fff;
    margin: 0 auto;
}
.footer{
    width: 100%;
    background-color: rgb(56, 210, 61);
    margin: 0 auto;
    min-height: 100px;
}
.sidebar{
    float: left;
    width: 189px;
    min-height: 600px;
    background-color: #ff77bb;
    padding-left: 10px;
    border-right: 1px dashed #fff222;
}

.right_side{
    float:right;
    width: 189px;
    min-height: 600px;
    background-color: #269520;
    padding-left: 10px;
    border-right: 1px dashed #fff222;
}

.content{
    /* float: left; */
    width: auto;
    min-height: 600px;
    background-color: #15ffff;
    margin-left:0 205px; 
    /* sidebar 200px+设计2个div间的间距5px */
}